Sealed battery for coordinate measurement machine

ABSTRACT

A coordinate measurement machine can include a battery positioned at least partially within the base of the machine. The battery allows operation of the coordinate measurement machine in locations that are remote from an AC power supply. The battery can be rechargeable and can be positioned in a battery adapter that serves as a battery charger. The coordinate measurement machine can also include a cover to enclose the battery within the base. The cover can include one or more sealing members to keep contaminants and other external objects away from the battery. The cover can be fastened to be base, for example, with bolts. The sealing members can be o-rings, gaskets, silicon membranes, seals, sealants, or another material. This sealed cover can meet or exceed industry standards for the protection of electrical components, such as ingress protection standard IP65 as administered by the International Electrotechnical Commission.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 60/796,973, entitled “SEALED BATTERY FOR COORDINATEMEASUREMENT MACHINE,” filed on May 1, 2006.

Also, this application hereby incorporates by reference theabove-identified provisional application, in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present application relates to measuring devices, and moreparticularly, articulated arm coordinate measurement machines formeasuring the coordinates of three-dimensional objects.

2. Description of the Related Art

Rectilinear measuring systems, also referred to as coordinate measuringmachines (CMM's) and articulated arm measuring machines includingportable coordinate measuring machines (PCMM's) have been described forgenerating geometry information from various objects and areas. Ingeneral, these instruments capture the structural characteristics of anobject for use in electronic rendering and duplication. One example of aconventional apparatus used for coordinate data acquisition comprises asupport and a moveable measuring arm made up of hinged segments to whicha contact-sensitive probe or remote scanning device is attached.

Geometry information or three-dimensional coordinate data characterizingthe shape, features, and size of the object may be acquired by tracingor scanning along the object's surface and contours. Probe or scanningdevice movement is typically tracked relative to a reference coordinatesystem resulting in a collection of data points and information that maybe used to develop an accurate electronic rendering of the object. Inconventional implementations, the acquired geometry information isprocessed by a computer capable of making use of the information tomodel the surface contours and dimensions of the object.

SUMMARY OF THE INVENTION

In one embodiment, a coordinate measurement apparatus comprises a baseconfigured to at least contain one or more removable batteries, a covermember configured to be secured to the base and one or more seal memberssituated between the base and the cover member. In one arrangement, thecover member of the coordinate measurement apparatus substantiallyencloses the removable battery. In another embodiment, the coordinatemeasurement apparatus further comprises one or more securement memberswhich are configured to secure the cover to the base. In yet anotherembodiment, the securement member is a bolt.

In some embodiments, the seal member situated between the base and thecover is a gasket, an o-ring, a silicone membrane, a seal, a sealantand/or the like. In another arrangement, the cover is configured toprevent moisture from contacting the battery. In one embodiment, thecover is configured to prevent dust from contacting the battery. Inanother embodiment, the seal member is attached to the cover. In yetanother embodiment, the cover is configured to satisfy at least oneindustry accepted standard for the enclosure of electrical components.In one embodiment, the cover is configured to meet the IngressProtection 65 (IP65) standard.

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects, features and advantages of the invention will becomeapparent from the following detailed description taken in conjunctionwith the accompanying figures showing illustrative embodiments of theinvention, in which:

FIG. 1 is a perspective view of an embodiment of coordinate measuringmachine;

FIG. 2 is a perspective view of another embodiment coordinate measuringmachine according to another embodiment;

FIG. 3 is a perspective view of a embodiment base portion of acoordinate measuring machine;

FIG. 4 is a front elevation view of the base portion illustrated in FIG.3;

FIG. 5 is a side elevation view of the base portion illustrated in FIG.3; and

FIG. 6 is a schematic cross-sectional view of the base portion takenalong line 6-6 of FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates one embodiment coordinate measuring machine (CMM) 10.In the illustrated embodiment, the CMM 10 comprises a base 20, aplurality of rigid transfer members 24, 26, 28, a coordinate acquisitionmember 30 and a plurality of articulation members 40, 42, 44, 46, 48, 50connecting the rigid transfer members 24, 26, 28 to one another. Eacharticulation member is configured to impart one or more rotationaland/or angular degrees of freedom. Through the various articulationmembers 40, 42, 44, 46, 48, 50, the CMM 10 can be aligned in variousspatial orientations thereby allowing fine positioning of the coordinateacquisition member 110 in three dimensional space.

The position of the rigid transfer members 24, 26, 28 and the coordinateacquisition member 30 may be adjusted using manual, robotic,semi-robotic and/or any other adjustment method. In one embodiment, theCMM 10, through the various articulation members, is provided with sevenrotary axes of movement. It will be appreciated, however, that there isno strict limitation to the number of axes of movement that may be used,and fewer or additional axes of movement may be incorporated into theCMM design.

In various embodiments, the coordinate acquisition member 30 comprises acontact sensitive member or probe 32 configured to engage the surfacesof a selected object and generate coordinate data on the basis of probecontact. Alternatively, the coordinate acquisition member 30 maycomprise a remote scanning and detection component that does notnecessarily require direct contact with the selected object to acquiregeometry data. In one embodiment, a laser coordinate detection device(e.g., laser camera) may be used to obtain geometry data without directobject contact. It will be appreciated that various coordinateacquisition member configurations including: a contact-sensitive probe,a remote-scanning probe, a laser-scanning probe, a probe that uses astrain gauge for contact detection, a probe that uses a pressure sensorfor contact detection, a probe that used an infrared beam forpositioning, and a probe configured to be electrostatically-responsivemay be used for the purposes of coordinate acquisition.

In other embodiments, one or more of the rigid transfer members 24, 26,28 comprise a composite structure that includes an inner portion and anouter exoskeletal portion. In such an arrangement, the inner portion ofthe rigid transfer members 24, 26, 28 are interconnected to one anotherthrough articulation members that provide the ability to position thecoordinate acquisition member 30 in a variety of different orientationsin three dimensional space. The outer portions surrounding the variousinner portions of the rigid transfer members 24, 26, 28 form anenvironmental barrier that at least partially encloses segments of theinner portions. In one aspect, the inner portions are configured to“float” inside the corresponding outer portions.

As is known in the art, the position of the probe 32 in space at a giveninstant can be calculated by knowing the length of each member and thespecific position of each of the articulation members 40, 42, 44, 46,48, 50. Each of the articulation members 40, 42, 44, 46, 48, 50 can bebroken down into a singular rotational degree of motion, each of whichis measured using a dedicated rotational transducer. Each transduceroutputs an signal (e.g., an electrical signal), which varies accordingto the movement of the 40, 42, 44, 46, 48, 50 in its degree of motion.The signal can be carried through wires or otherwise transmitted to athe base 20. From there, the signal can be processed and/or transferredto a computer for determining the position of the probe 32 in space.

In one embodiment, the transducer can comprise an optical encoder. Ingeneral, each encoder measures the rotational position of its axle bycoupling is movement to a pair of internal wheels having successivetransparent and opaque bands. In such embodiments, light can be shinedthrough the wheels onto optical sensors which feed a pair of electricaloutputs. As the axle sweeps through an arc, the output of the analogencoder can be substantially two sinusoidal signals which are 90 degreesout of phase. Coarse positioning can occur through monitoring the changein polarity of the two signals. Fine positioning can be determined bymeasuring the actual value of the two signals at the instant inquestion. In certain embodiments, maximum accuracy can be obtained bymeasuring the output precisely before it is corrupted by electronicnoise. Additional details and embodiments of the illustrated embodimentof the CMM 10 can be found in U.S. Pat. No. 5,829,148, the entirety ofwhich is hereby incorporated by reference herein.

In one embodiment, the base 20 of the CMM 10 may be situated on asupport surface, such as a table, floor, wall or any other stablesurface. In another embodiment, as shown in FIG. 2, the base 20A may bepositioned on a mobile unit 14, allowing the CMM 10A to be convenientlymoved from one location to another. In such arrangements, the base 20Amay be secured to the mobile unit 14 in a fixed manner (e.g. bolted,fastened or otherwise attached at one or more locations). Further, themobile unit 14 may be configured with retractable or drop-down wheels 16that facilitate in moving the CMM 10A. When properly positioned at thedesired location, the wheels 16 may be retracted and rigid support legs(not shown) may be used to secure the CMM 10A in a fixed and stableposition in preparation for the acquisition of coordinate data.Additional details of this embodiment of the CMM 10 can be found in U.S.Patent Publication 2005-015012, the entirety of which is herebyincorporated by reference herein.

FIGS. 3-6 are front perspective, front, side and cross-sectional viewsof an embodiment of a base portion 20B, which can be used in combinationwith the CMM 10, 10A embodiments described above or other CMM devices.In the illustrated embodiment, the base portion 20C includes a battery60 (see FIG. 6) that is positioned at least partially within areceptacle 61 in the base 20B to supply a portion or all of thenecessary electrical output to operate the device. The use of batteries60 is particularly useful for portable CMMs that may not have easy orconvenient access to a standard AC power supply during use.

In the illustrated embodiment, the battery 60 can be removed from thebase 20B for replacement, external recharging or any other purpose. Forcost-savings and other practical considerations, the battery 60 ispreferably rechargeable. Types of rechargeable batteries can includenickel cadmium (Ni-Cad), nickel metal hydride (Ni-MH), lithium batteriesor the like. Alternatively, those of skill in the art recognize thatsingle use batteries may also be used. It will be appreciated that asingle CMM may include two or more batteries 60. In addition, inmodified embodiments, the one or more batteries 60 may be situated inany other suitable portion of the CMM besides the base 20B.

In an embodiments, rechargeable batteries used in a CMM device may beadvantageously housed within a battery adapter that also serves as abattery charger. Thus, in one embodiment, the battery 60 is rechargedwhile secured within the CMM 20C by simply attaching the CMM 20C to anexternal power supply (e.g., AC power source). In another embodiment,the CMM 20B can be configured so that the battery 60 is recharged by anexternal charger.

In the illustrated embodiment, the battery 60 can be configured to bepositioned within receptacle 61 in the base 20C or another other part ofthe CMM 10C. With particular reference to FIG. 6, the battery 60 can bepositioned in the receptacle 61 near the bottom of the base 20B on afront portion of the CMM 10C. To ensure that the battery 60 has beenproperly positioned within the slot or adapter, a snap fit or anothertype of positive engagement or locking mechanism can be optionallyprovided.

As shown in FIG. 6, in the illustrated embodiment, the CMM 10C includesa cover 62 configured to enclose the battery 60 within the base 20B. Thecover 62 is preferably sized and shaped to snugly fit over the battery60 and the adjacent surfaces of the CMM 10B so as to completely concealthe battery within the base 20B. In one embodiment, one or more sealingmembers 66 are included between the cover 62 and the outer surface ofthe base 20B or other surface of the CMM 10B. This is particularlyimportant for CMMs that are used in environments where contaminants andother outside elements (e.g., dust, water, etc.) are present. In suchsituations, it is important to keep contaminants away from electricaland other sensitive internal components of the CMM 10B. Therefore, thebattery 60, the electrical contacts and any other internal componentsare protected from corrosion and/or other similar damage resulting fromexposure to the elements. Further, with or without the sealing members66, the cover 62 can help to prevent the accidental disconnection of thebattery 60 from the corresponding electrical contacts. In addition, thecover 62 can protect the battery 60 from damage resulting from theaccidental contact with other objects during operation of the CMM 10B.

The one or more sealing members 66 can include o-rings, gaskets,silicone membranes, seals, sealants and/or any other material.Typically, the sealing members 66 are made of a compressible material(e.g., rubber, Viton, silicone, etc.) to further enhance the sealingeffect between the cover 62 and the adjacent surfaces of the CMM 10B.The battery cover 62 may be constructed of one or more rigid orsemi-rigid materials, including, but not limited to, aluminum, steel,stainless steel, iron, fiberglass, plastic, polycarbonate, acrylonitrilebutadiene styrene (ABS), polystyrene or the like. In some arrangements,two or more different materials may be used to construct a single cover62. Further, the cover 62 can include a solid, clear, translucent,transparent and/or other type of construction.

As illustrated in FIGS. 3-6, in the illustrated embodiment, the cover 62can be connected to the base 20C using two fasteners 64. In thepreferred embodiment, the fasteners 64 comprise bolts 64 that can beremoved with a tool (e.g., an Allen Wrench or Hex Key). In this manner,the cover 62 is not easily removed or dislodged. Those of skill in artwill appreciate that fewer or more than two fasteners 64 can be used andthat the position of the fasteners 62 can be modified. For example, inFIG. 6, a fastener is shown being position on an upper, central portionof the cover 62. In certain embodiments, the use of the fasteners 64 incombination with the sealing member 66 can eliminate or reduce theamount of dust, water, other fluids and any other contaminants thatcontact the battery 60 and the other internal components of the CMM 10C.Thus, in one embodiment, the battery 60 is completely concealed withinthe base 20C.

In some embodiments, the cover is advantageously designed to meet and/orexceed one or more industry-recognized ratings for the protection ofelectrical components (e.g., IP65). Such industrial standards, asadministered by the International Electrotechnical Commission (forIngress Protection (IP) standards), National Electrical ManufacturersAssociation (NEMA) and others, ensure that a cover 62 or otherelectrical housing is adequately designed for a particular environment.For example, there are different Ingress Protection (IP) ratings forprotection against exposure to moisture (e.g., dripping water, sprayingwater, immersion, submersion, etc.). In one embodiment, the cover 62 andother components of the battery protection system are capable ofachieving a IP62 rating or better. The various characteristics (e.g.,size, material, thickness, shape, etc.) of the cover 62 and the sealingmembers 66 can be modified to satisfy the desired level of protection.

The various devices, methods, procedures, and techniques described aboveprovide a number of ways to carry out the invention. Of course, it is tobe understood that not necessarily all objectives or advantagesdescribed may be achieved in accordance with any particular embodimentdescribed herein. Also, although the invention has been disclosed in thecontext of certain embodiments and examples, it will be understood bythose skilled in the art that the invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses and obvious modifications and equivalents thereof.Accordingly, the invention is not intended to be limited by the specificdisclosures of preferred embodiments herein.

1. A coordinate measurement apparatus comprising: an articulated armhaving a first end, a second end, a plurality of jointed arm segmentstherebetween, each arm segment including at least one positiontransducer for producing a position signal; a measurement probe attachedto said first end of said articulated arm; a base coupled to the secondend of the articulated arm, the base comprising a top side, a bottomside, a front side, a rear side, a left side and a right side, the basefurther comprising receptacle positioned on the front side of the base;a battery positioned within the receptacle such that a first portion ofthe battery lies within the receptacle and a second portion of thebattery extends outside the receptacle; a cover member configured to besecured to the base and completely conceal the battery within the base,the cover member defining an enclosed space configured to receive thesecond portion of the battery and a front face configured to abut afront side of the base; and at least one compressible seal member atleast partially situated between the front side of the base and thefront face of the cover member; wherein the cover member substantiallyencloses the at least one removable battery.
 2. The coordinatemeasurement apparatus of claim 1, further comprising at least onesecurement member configured to secure the cover to the base.
 3. Thecoordinate measurement apparatus of claim 2, wherein the securementmember is a bolt.
 4. The coordinate measurement apparatus of claim 1,wherein the at least one seal member is selected from the groupconsisting of: gasket, o-ring, silicone membrane, seal and sealant. 5.The coordinate measurement apparatus of claim 1, wherein the cover isconfigured to prevent moisture from contacting the battery.
 6. Thecoordinate measurement apparatus of claim 1, wherein the cover isconfigured to prevent dust from contacting the battery.
 7. Thecoordinate measurement apparatus of claim 1, wherein the at least oneseal member is attached to the cover.
 8. The coordinate measurementapparatus of claim 1, wherein the cover is configured to satisfy atleast one industry accepted standard for the enclosure of electricalcomponents.
 9. The coordinate measurement apparatus of claim 8, whereinthe cover is configured to meet Ingress Protection 65 (IP65).